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Triumph unit 650 Motor with no numbers

6059 Views 20 Replies 13 Participants Last post by  bongoman
So, I picked up this motor, I think is early -mid 60's, unit 650, with no numbers at all on the cases. Just virgin casting as far as I can tell. My question is this: did Triumph always put numbers on engine cases? If not, when did they start? I'm in NH, so as long as I drop this lump in a frame with good numbers, I can register the bike, so that's not my issue or question. Just wondering how a motor shows up with no numbers anywhere. No grind off, no restamp. Just raw casting.

Will try to post pics later. And if this was covered in another thread, I couldn't find it.....
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Factory replacement cases were blank with the intention that the dealer would stamp in the number of the old cases being replaced. It did not always happen. I have several sets of blank cases. Depending on your local it may or may-not matter. Some places want both an engine number and frame VIN. Some don't care. Just be sure before you jump in ! And ALL factory built bikes had numbers on the cases, from the beginning of time!
Thanks Rubone. I got a deal on this, so am now the proud owner. Here are some pictures. anyone want to hazzard a guess at the year?

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You got a vented rocker cap. No breather on the primary side and no clutch cable cover or filler hole on the kicker cover.,I dont know enough but you might have mismatched parts .
How do you put gear fluid in this one? Later models have the crankcase breather I think , cool Sig..
Oh that is the bottom of the sea model. Mid to late 60's is all i got for you. Pull a bolt out and try to see if the threads are British standard 1967 and down or SAE bolts 1968 and up.
Looks like about '66 to me,with the rocker boxes reversed. If you pull the rocker boxes to put them right,there will be an embossed number on the head(under the ex. RB.) that is the year the head was cast. The year model is usually one year later. As in if the number is "65", it is a 66 motor. Jack
65-67 based on primary and kicker covers and the timing plug behind the cylinder.
you should be good as long as you have a frame with a good title.
Thanks for all the comments and suggestions. I got it up on the motor stand tonight. Can't wait to rip into it.
You'll notice that there's no filler plug for the geabox.It is still possible to fill it,if you remove the clutch cable and squirt oil in there.
Up to '67 the filler was on top of the box.'68 and later filled through the outer cover,near the clutch cable.
Looks like it was a pre-'68 engine,that now has '68 or '69 cases (probably threw a rod).
WARNING:Check if there are oil-fed exhaust tappets,and check what type.If they have a small 3/32" flat on the oil hole,you don't need the metering dowel at the crankcase/timing case joint;it only needs a plain hollow dowel near the relief valve.
If the flat on the tappet stems is much bigger,you have almost no crank oil pressure without the metering dowel.
I have a set of cases with no numbers as well just like in the pictures here. No cast in boss with the triumph logo, and no grind marks. I have been told more than once, both ways, that there must be a cast boss where the numbers were to be stamped by the dealer, or there was no cast boss. Minnesota requires engine numbers one title transfers, so this engine is sitting. It came with a frame with 66' numbers but with no title...a common lament. So is there a definitive answer to boss or no boss?
That I don't know. What I'm told here and by a local dealer is the case without boss or numbers is a repair item. It Is supposed to get the number from the broken case stamped on it by the dealer or repair shop and that did not always happen. I guess I'm lucky to be in NH, where they don't title bikes that old, and I can register it with the frame number and a bill of sale on a napkin.
At least 68 and up have the breather on top rear of the the primary, i t know for sure im looking at one now.
Approx. Sept.1968(1969 Model Year) the raised pad for the numbers appeared. The breather out the rear top of the primary started with the 1970 models(approx. sept.1969). Jack
my '68 has raised pad for breather on primary...has removable timing cover on primary cover..whitworth thread...and the gearbox is filled thru the kicker cover.... oiled tappets on ex side

my '66 has no raised pad for breather on primary or removable timing cover....whitworth thread of course...gearbox filled on top of cases in the rear of cylinder

my '65 is in a box up on a shelf.....and exploded at least once in its life....wiped out the inside of cases tach drive side...but did not break cases...was rebuilt..i do not trust this one is all original...

Where's Tony the Torch....or Wes....they will straighten us out....
My guess is that engine was 67 and before motor that blew up, the un-stamped non raised number pad without a trans filler plug would say 1968, but the non-filler plugged kicker cover is 67 and before.
some mid year 68's had the relocated timing plug down in the front of the engine and those are easy to spot as 1968's.
Chances are they used the original head on the replacement cases so like Jack says pull the intake rocker box and look at the date stamp, you gotta switch them back around anyway.
Tear down starts this weekend. Will take pics along the way. This is fun, like a puzzle, shrouded in mystery, wrapped in an enigma, veiled by uncertain history....
i have a 64 early, has no provision for crank timing hole, they added this late in 64 . so i would hazard a guess 63 or 64 unit . the crank and oil pressure release valve kinda suggest the same. the books are never in adgreement to details as i have 8 diff books on the unit bonnies and only one even mentions the lack of crank timing hole . an antique shop book as well. let me know as i bet myself a silver dollar.
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